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The construction of the Savio railway tunnel caused an unexpectedly large decrease in the groundwater heads in part of the observation points in the vicinity of the railway tunnel after the completion of the tunnel construction work. The study aimed to investigate the ability of the groundwater model to forecast such groundwater drawdown caused by a railway tunnel in the urban areas of East Hakkila, Kaskela and Hakunila. The uncertainty of the groundwater model and its sensitivity to certain parameters were studied and analyzed. The groundwater model was built using the GMS (Groundwater Modeling System) numerical groundwater modeling program. For the groundwater flow model, the bedrock mesh was built in Leapfrog Geo - program based on gravimetric measurements and rotary drilling. The groundwater model was calibrated manually and automatically to correspond to the groundwater heads measured in the area. The circumstances after the construction of the railway tunnel were then simulated. The model-calculated groundwater heads were compared to the observed groundwater heads and the observed tunnel leakage. Sensitivity analysis was performed for the horizontal conductivity parameters and recharge parameters of the model. The groundwater model before the construction of the tunnel mimicked the measured groundwater heads and flow directions in the study area. The simulation of the time after the construction of the tunnel caused groundwater drawdown of 0-16 meters at 0-730 meters from the railway tunnel. In the simulation of the time after tunnel construction, the groundwater heads calculated by the model differed by 0,01-24 meters from measured groundwater heads. According to the results of the sensitivity analysis, the model was most sensitive to changes in the horizontal conductivity of the upper bedrock layer and granite. The recharge parameters and soil layer had a marginal impact on the groundwater model. The uncertainty of the model was affected by the few measurement points in relation to the size of the area and the absence of field measurements of the hydraulic conductivity of the parameters. To reduce the uncertainty, the model should be calibrated based on the measured conductivity values of the bedrock. Despite the uncertainty, computational models give indications of the direction of change and are important tools in questions related to nature and the built environment.

Tutkimus suoritettiin Lammin Tullinkankaan pohjavesialueelta. Tutkimusalueelta valittiin kaksi metsikköä, jossa toisessa pohjavesi on noin metrin syvyydellä maanpinnasta (sarja 'vedellinen') ja toisessa noin kahden ja puolen metrin syvyydellä (sarja 'vedetön'). Oletuksena oli, että pohjaveden pinnankorkeus vaikuttaa männyn kasvuun alueella, jossa pohjaveden pinta on lähellä maanpintaa. Sarjoja verrattiin toisiinsa sekä ilmasto- ja pohjavesitietoihin. Molemmilta alueilta otettiin yhteensä n. 20 lustonäytettä, joista muodostettiin omat ristiinajoitetut lustokronologiat. Vedellisen sarjan kronologia kattaa vuodet 1872–2008 (137 vuotta) ja vedettömän sarjan kronologia vuodet 1958–2008 (51 vuotta). Vedellisen alueen männyt korreloivat negatiivisesti touko- ja kesäkuun pohjaveden pinnankorkeuden kanssa sekä positiivisesti kesäkuun sademäärän ja helmikuun lämpötilan kanssa. Vedettömän alueen männyt korreloivat negatiivisesti toukokuun sademäärän ja marraskuun lämpötilan kanssa sekä positiivisesti maaliskuun sademäärän kanssa, mutta eivät ollenkaan pohjaveden pinnankorkeuden kanssa. Vedellisen alueen kronologiaa käytettiin monimuuttujaregressiossa selittävänä tekijänä selittämässä toukokuun pohjaveden pinnankorkeutta. Vedellisen kronologian ja toukokuun pohjaveden pinnankorkeuden välisen mallin korjattu selitysaste oli 0,37 ja korrelaatiokerroin 0,62. Ristiinvalidoidutu rekonstruktiomalli kattaa vuodet 1880– 2002. Rekonstruoidusta pinnankorkeusmallista rekonstruoitiin spektrianalyysin avulla tilastollisesti merkitsevä 23,81 a jaksollisuus.

Hallitustenvälinen ilmastonmuutospaneeli IPCC määrittelee Pohjois-Atlantin subpolaaripyörteen ilmaston käänne-elementiksi, joka voi joutua ilmaston muutoksen seurauksena toiseen tilaan. Tässä työssä tarkastellaan ensin tieteellisten artikkelien pohjalta subpolaaripyörrettä ja sen vuorovaikutusta muun meren, sekä ilmakehän kiertoliikkeen kanssa. Sen jälkeen muodostetaan CMIP5-projektin (Coupled Model Intercomparison Project 5) ilmastomallien pohjalta kaksi malliryhmää. Toisessa on kolme mallia, joissa subpolaaripyörteen syvänveden muodostus romahtaa, toinen on vertailuryhmä. Subpolaaripyörteen romahdus näyttää todennäköisemmältä kuin CMIP5-malliryhmien kokoa vertailemalla voisi päätellä ja romahdus voi tapahtua jo pienimmällä RCP2.6-skenaariolla. Suunnilleen yhtä todennäköistä, kuin yksi romahdus, on useampi nopea subpolaaripyörteen heikkeneminen, joiden välissä subpolaaripyörre voimistuu uudelleen. Tämä ilmiö voi lisätä tulevaisuuden ilmastossa vaikeasti ennakoitavaa vuosikymmenten välistä vaihtelua. Subpolaaripyörteen romahduksen ilmastovaikutukset ovat suurimmat arktisella alueella, Pohjois-Atlantilla ja Euroopassa. Se heikentäisi pohjoisen napa-alueen lämpenemistä, joka muuten on paljon voimakkaampaa kuin maapallon keskimääräinen lämpeneminen. Euroopassa ilmiö hillitsee ilmastonmuutoksen aiheuttamaa lämpenemistä ja voi muuttaa ilmakehän keskimääräistä kiertoliikettä. Suurimmat vaikutukset keskittyvät kuitenkin subpolaaripyörteen alueelle.

Methane is an important greenhouse gas in the global atmosphere and its concentration has more than doubled compared to preindustrial times. Fresh water lakes and streams are substantial sources of methane. However, the estimations of their role in the global methane budget vary significantly and not until the 21st century has the understanding of their role as substantial methane sources increased. In the boreal zone, lakes produce as much as 30 % of the methane emissions. In this study, we examine spatial and temporal changes in methane fluxes from northern boreal lake Pallasjärvi and from a small stream located in its catchment area between June and November of 2020. We also examine the factors that explain the spatial and temporal changes in the methane fluxes, both lake and stream. Lake and stream methane fluxes were measured every other week between June and August, once a week in September, and once in the beginning of November using the chamber method. During the chamber measurements we also measured water surface temperature. Furthermore, at the stream sites we measured the water flow rate. At the lake measurement points we measured the water depth in November, which we calibrated to apply to the entire measurement period using water pressure logger. In March 2021, we measured the depth of the sediment layer at the lake sites. We also used CORINE-landcover data to model stream methane fluxes and for the lake, we used Finnish Meteorological Institute’s wind speed and direction dataset. We used these variables in order to explain the spatial and temporal variation of the lake and the stream methane fluxes using correlation analysis and linear mixed models. In this study, we find that water surface temperature, water depth, and wind were significant variables in explaining the lake methane fluxes. Respectively, landcover and surface water temperature explained the stream methane flux. From a temporal perspective, the strongest fluxes were measured between June and July at the lake sites and August and the beginning of September at the stream sites. Methane fluxes were divided spatially in two different groups at both lake and stream sites. At the lake sites, the strongest fluxes were measured in the shallow Pallaslompolo area and the weakest at the larger and deeper main basin of the lake. At the stream sites, the fluxes were also divided in two groups, the upstream’s weak fluxes and the downstream’s strong fluxes. According to the results, the temporal change of flux in the lake area is controlled by the changes in the factors underlying the methane production, and the differences in the lake basin depth control the spatial change of flux. The temporal change of stream methane flux depends on the changes in the methane production in the stream and its catchment area, while the spatial change depends on the changes in the landcover along the stream. However, more research and data are needed about the lake sediment layer temperature and oxygen levels, the water methane concentration, and stream catchments with different landcovers, which all impact the methane fluxes.

Schwarzin lemman mukaan jokainen origon kiinnittävä analyyttinen yksikkökiekon D itsekuvaus f on joko kierto tai se kutistaa pisteen z \neq 0 etäisyyden origoon. Kun D tulkitaan hyperbolisen geometrian mallina ja f tämän mallin mukaisena kuvauksena, saadaan hieman heikommilla oletuksilla vahvempi tulos: hyperbolisen metriikan suhteen jokainen analyyttinen yksikkökiekon itsekuvaus on joko isometria tai kutistus. Tulos tunnetaan Schwarzin-Pickin lemmana, joka todistetaan tässä tutkielmassa. Ennen Schwarzin-Pickin lemmaa tutkielmassa määritellään Poincarén kiekkomalli hyperboliselle geometrialle ja osoitetaan sen toteuttavan hyperbolisen version Eukleideen paralleeliaksioomasta. Lisäksi määritellään tarvittava hyperbolinen metriikka, osoitetaan sen indusoiman etäisyyskäsitteen ominaisuuksia sekä havainnollistetaan niitä esimerkein. Tutkielman tärkeinä apuvälineinä käytetään Möbius-kuvauksia, jotka kuvaavat hyperboliset suorat hyperbolisiksi suoriksi. Erityisesti osoitetaan, että kiekon D konformiset automorfismit ovat tunnettua muotoa olevia Möbius-kuvauksia, jotka muodostavat ryhmän kuvausten yhdistämisen suhteen. Automorfismien osoitetaan myöhemmin olevan täsmälleen samoja kuin hyperboliset isometriat, minkä avulla saadaan helposti osoitettua useita etäisyyttä koskevia väitteitä. Schwarzin-Pickin lemma todistetaan yhdistämällä kuvaus f kahden sopivat ehdot täyttävien automorfismien kanssa ja soveltamalla Schwarzin lemmaa saatuun yhdisteeseen. Tutkielman lopuksi todistetaan kaksi Schwarzin-Pickin lemmalla saatavaa tulosta, joista ensimmäisen mukaan aiemmin määritelty hyperbolinen metriikka on vakiokerrointa vaille ainoa, jonka suhteen automorfismit ovat isometrioita. Toinen tulos on Schwarzin-Pickin lemman eräs vahvempi muoto, joka antaa tiukemman ylärajan kuvauksen f kuvapisteiden väliselle hyperboliselle etäisyydelle.

Petroleum hydrocarbons (PHCs) and heavy metals are common soil contaminants, which when released in the environment have the potential to damage plants as well as endanger the health of both humans and animals. Investigating these contaminations for cleanup purposes is therefore important, and developing new rapid techniques to aid in this process would be beneficial. VNIR-SWIR (350–2500 nm) reflectance spectroscopy is a well-known method that has been shown to be a promising tool for the rapid and costeffective mapping and monitoring of various soil contaminations. However, previous studies have mainly focused on the spectral features of soil contaminants; the anisotropic nature of reflectance and polarization have been largely ignored. Characterization of these reflectance properties has the potential to provide valuable additional information, that can be used to improve remote-sensing methods and help develop reflectance models for the quantitative and qualitative analysis of contaminants in soil. To study the bidirectional reflectance and polarization properties of petroleum hydrocarbons and lead, the Finnish Geodetic Institute Field Goniospectrometer (FIGIFIGO) was used to measure samples artificially contaminated with diesel, motor oil and lead in the laboratory as well as lead contaminated soil and vegetation at Suomenlinna, Finland. In total, 23 samples were measured. It was confirmed that petroleum hydrocarbons can be detected from their characteristic absorption bands, and that the 1730 nm band is the most significant for this purpose. However, clay minerals appeared to considerably lower the intensity of these bands and affect the reflectance. Despite this, hydrocarbon absorption features were successfully detected from all samples at a lowest measured concentration of 0.5 wt.%. The polarization in the backward direction was found to decrease when diesel or motor oil was added, while the polarization increased in the forward direction on low zenith angles. In order to better understand the relationships between clay, water, hydrocarbon and quartz contents and their combined effects on the reflectance, more studies are needed. The reflectance and polarization of the laboratory Pb samples were found to increase significantly in the forward direction, while the polarization decreased in the backward direction in the SWIR region. This characteristic, if investigated further, could prove useful for the detection of heavy metals in soil. Lead was not reliably detected from the field samples, but more controlled studies on the relationship between soil contaminations and polarization properties of vegetation should be considered.

In the 21st century, there is an intensified social-political mindset, where people are no longer separated from nature. As a result concepts and theories of ecological research become part of regional policy and spatial planning. At the same time, ecological knowledge, technology orienta- tion and the economic potential created by them form an equilibrium between them. It may, depending on the context, turn to the barrier or benefit of the economy. Talking about the ecologicalization of politics which affecting all spatial planning levels in Finland. It has caused to conflicts in land use planning, when you try to take into account the importance of the nature of knowledge and to protect the directive species, such as flying squirrels. The aim of the study is to find out about the written material and the interviews with the peasants: what the flying squirrel conservation is all about and how it related to the ecologicalization of politics and what are the reasons for the species's conservation zoning conflicts and how can they be solved? As a case study, I will look at the Tramway project in Tampere, from the point of view of the flying squirrel’s conflict and ecologicalization of politics. At the same time, the aim is to develop the concept of ecologicalization of politics and to produce new information about the prevailing greenish social change. Flying squirrel is protect by a politically determined decision in the European Union area and it’s the small-scale night-life mammal which occurs grown up in mixed forests. In the EU, species occur in Finland and small quantities in Estonia and possibly in Latvia. Given that the EU is responding to the problem of state protection, the common species in Finland is the directive specie which requires special protection. The Habitats Directive has been implemented in Finland's National Nature Conservation Act at the end of the 1990s and the directive prohibits the eradication and deterioration of breeding and resting places of the species. In addition, the guiding regulation of the protection of the flying squirrel is included in the Land Use and Building Act, Land Act and Forest Law. Despite the protection of the flying squirrel population is estimated declined from the period after the Second World War in Finland, but the species is classified as held for an eye only. The calculation of population classification has been criticized. The entry into force of the Land Use and Building Act in 2000 was an important legal reform for the protection of the flying squirrel. A key change in the law had made land use planning objectives addition of "conservation of biodiversity and other natural values". In addition, the sections on increasing interaction and impact assessment of zoning have made the planning process more transparent and added the importance of nature enthusiasts. Influencing people often involves complaining about patterns, which is unfortunate. It offers residents the opportunity to influence the surrounding environment and protect nature, such as flying squirrels. Grown up in mixed forests of the flying squirrel favored often set in the cities, because the mixed forests have reduced and fragmented due to forestry in outside the cities. Urban forests directed to a plurality of user requirements, because it can be flying squirrel homeforests, residents recreational use, commercial forest and zoning residences area. Flying squirrel in the comfort of urban forests is challenging because growing cities expand and condense. The protection of the flying squirrel has caused conflict’s situations in many cities. An example of this is Pirkanmaa long flying squirrel conflict history and its recent case in Tampere’s tram project. The tramway is a matter of valuing of the political decision-making, where the construction the tram means ignoring another environmental value, nature conservation. The flexible nature of ecologicalization of politics is manifested in a tramway project, when ecological knowledge of the flying squirrel turns against economic goals and co-operation between actors. For people who benefit from economic growth and for the city's growth, the flying squirrel is a financial slowdown which complicates regional cooperation in Tampere urban area. Although the protection of flying squirrel is not just a matter of protecting the city's local level, but also regional co-operation, as the dynamic species moves away from the municipal boundaries.

Ocular drug delivery is a complex field of pharmaceutics due to the unique conditions on the eye surface. Currently used drug carriers have disadvantages like irritation and blurred vision, and moreover, the bioavailability of drug formulations is low. This research aimed to synthesize novel and safe drug carriers for ocular drug delivery that could prolong retention on the eye and resist a tear washout effect. The drug carrier consists of a gellan gum that is an anionic polysaccharide having a property for in situ gelling. Gellan gum was modified with short poly(2-ethyl-2-oxazoline) grafts that have shown to have minimal unspecific organ deposition and rapid renal excretion. The choice of synthetic procedure, solvents, and reagents was dictated by biocompatibility of the materials and possible medical application. Graft copolymers were synthesized in a two-step synthetic procedure in which at first 2-ethyl-2-oxazoline was polymerized via cationic ring-opening polymerization. Next, living polymer chains were combined with deprotonated gellan gum to attach grafts onto the gellan backbone. Grafting was performed in three different degrees of grafting by changing poly(2-ethyl-2-oxazoline)-to-gellan mass ratio in the feed. Grafted copolymers were studied by nuclear magnetic resonance spectroscopy (NMR) and infrared spectroscopy (IR) and by thermogravimetric analysis (TGA). In addition, the molecular weights of PEtOx grafts were determined by size exclusion chromatography (SEC). Based on the results, synthesized copolymers had different degrees of grafting. The thermogravimetric analysis demonstrated a two-step degradation process for copolymers, in which the steps and weight losses correlated well with the grafts content. The diffusion-ordered spectroscopy (DOSY) proved that the grafting had actually taken place, but a lower diffusion coefficient for copolymer in relation to the diffusion of a native gellan revealed degradation of the backbone.

4D printing is becoming increasingly investigated as it is emerging as a pioneering method for biofabrication. By implementing programmable shape changing thermoresponsive hydrogels in bioink formulations, a 4D response can be achieved, which can be manipulated to print artificial organs and tissues. The limited selection of biocompatible thermoresponsive hydrogels, accompanied by the mechanical weakness of hydrogels have restricted the mainstream application of this technology in the field of bioprinting. The most commonly studied thermoresponsive polymer is poly(N-isopropylacrylamide), but it is understood that the monomer N-isopropylacrylamide exhibits cytotoxicity at low concentrations. The primary goal of this study is to investigate poly(2-substituted-2-oxazoline) macromonomers as potential alternatives to poly(N-isopropylacrylamide), and the secondary goal is to investigate microgels as an additive in crosslinked networks to enhance hydrogel mechanical strength. The results in this work indicate that poly(2-n-propyl-2-oxazoline-co-2-ethyl-2-oxazoline) is a promising candidate for 4D printing, because it’s LCST can be fine-tuned by altering the monomer ratio. However, it still requires further investigation as it requires an acrylamide comonomer to crosslink, and it also has compatibility issues with commercial printing additives like Pluronic F127. The addition of 2 wt.% microgel also showed promise as it enhanced the hydrogels mechanical strength over threefold.

This thesis presents and proves Pólya's enumeration theorem (PET) along with the necessary background knowledge. Also, applications are presented in coloring problems, graph theory, number theory and chemistry. The statement and proof of PET is preceded by detailed discussions on Burnside's lemma, the cycle index, weight functions, configurations and the configuration generating function. After the proof of PET, it is applied to the enumerations of colorings of polytopes of dimension 2 and 3, including necklaces, the cube, and the truncated icosahedron. The general formulas for the number of n-colorings of the latter two are also derived. In number theory, work by Chong-Yun Chao is presented, which uses PET to derive generalized versions of Fermat's Little Theorem and Gauss' Theorem. In graph theory, some classic graphical enumeration results of Pólya, Harary and Palmer are presented, particularly the enumeration of the isomorphism classes of unlabeled trees and (v,e)-graphs. The enumeration of all (5,e)-graphs is given as an example. The thesis is concluded with a presentation of how Pólya applied his enumeration technique to the enumeration of chemical compounds.